Device for applying liquid adhesive to paper and similar materials



Sept. 14, 1937. A, wlNKLER'E-r AL 2,093,221 DEVICE ROR APPLYING LIQUID ADHESIVE TQP'APER'AND SIMILAR MATERIALS Filed OCT., 3, 1955` 2 SheetS-Shet l l v/A/VE/YTO/fs j Az F2950- nf//v/:L El May: DUN/VE B/E Q SePf- 14, 1937. A. wlNKLER Erm. 2,093,221

DEVICE FOR APPLYING LIQUID ADHESIVE T0 PAPER AND SIMILAR MATERIALS Filed oct. s, 1955 2 sheets-sheet 2 Patented Sept. 14, 1937 PATENT ori-ics sposati' nEvron Foa APPLYING LIQUID Annnslva To PAPER AND summa MATERIALS Alfred Winkler and Max nummer, Named,

Germany 4 Application october 3, 1935,'sem1 No. In Germany May l25, 1934 L The invention relates to a device -for applying liquid adhesive to paper' and similar materials. In particular it is an object of the invention to enable liquid adhesive of all kinds to be'applied satisfactorily by the so-called echelon or stepped layer process even in cases in which blanks for the production of envelopesv or bags `or .other sheets of paper or similar material which are laid, in stepped arrangement, one on top of another and one beyond another with their edges a given' distance apart, have to be provided, in

` ment being shown, Vfor instance, in the drawing of application Serial No. 13,510, led March 28,

`1935, for Letters Patent of the United States of America) the layer of sheets 'canbe guided along past one of the adhesive apply'ing devices in such a fashion that those surface portions of the sheets onvone. side of the saidiayer which, by

reason of the stepped arrangement, are exposed,

so that -they can be served with adhesive, lie to the rear, having regard to the direction of motion of the layer. For the application of the adhesive to these rearwardly located surface portionsof the sheets one of the adhesive applying devices ordinarily used for the stepped layer gumming process can be employed. When, however, after leaving such anadhesive` applying de;V

vice, the layer of sheets is carried along further in the same direction and in the same 'stepped formation the exposed surfaces upon the other*l side of the layer, which surfaces also haveto take a coating'of adhesive, must, of necessity, lie one ahead of another, having regard to the direction of motion -o f the layer. Consequently, .the outer edges of these exposed surface portions of the sheets are the foremost parts to encounter the device which applies adhesive to this side of the layer. Adhesive applying devices as commonly used in the stepped layer gumming process cannot, therefore, be employed in this case, as the advanced edges of the sheets would collide with the edges of such devices, causing damage tothe blanks and .frequent derangements in the working of the machine as a whole.

On thisv account, for the purpose under 'consideration, devicesv have been proposed'inA which the application of the adhesive is effected bya rotating applier roll, which maires contact withthe' stepped layer of sheets and which takes up the adhesive from a d ipper roll running in'an adhesive container. y 5 Such adhesive applying devices, apart from` their relativelycomplicated construction, have the disadvantage ythat lthey require very careful minding. Iglrst and foremost, care must be taken that, when the machine asa whole is tem- 10 poraril'y shut down, so that the stepped layer of sheets is also stopped, the adhesive shall not dry up on the rolls of the adhesiveapplying device, as this would jeopardize the satisfactory working of the latter. Consequently, when the 15 complete machine in which theyv are employed is temporarily shut down, these adhesive applying devices must not only continueto run uninterruptedly, so that the adhesive may not have an opportunity of solidifying on the rolls, but they ai)l ing the so-called dry adhesive for plastic gumming as this dries with extraordinary rapidity when, in the form of a thin layer on the rolls, it is exposed to air; The rapidly drying adhesive substance then assumes a viscous con'- 8l sistency and, under the rubbing action of the rolls, turns into more or less fine crumbs which deposit themselves on the surfaces of the blanks Vto befprovided with adhesive coatings. An adhesive coating permeated in this way with 40. crumbs is naturally unsatisfactory and, in most f of the layer of sheets, use of this 'device not only 50 avoids disturbances in working' due to the sheets arriving at the devicev edgerst but also obviates the aforementioned defects of adhesive applying devices operating with rolls.

Important features of the adhesive applying u llies close against the layer of sheets. The course.

or path followed by this slit from the interior of the container to its outlet opening on the layer of sheets, is such that the said path forms an acute angle with the direction from which the stepped layer of sheets advances.- Furthermore, that outer surface of the adhesive container which is turned towards the stepped layer of sheets, hasV a rounded off or inclined part in front of the adhesive outlet slit onthe sideffrom which the laye.` of sheets advances, this part gradually receding from the said layer the farther it goes from the edge of the outlet slit.

One result of this construction of the adhesive applying container is that the adhesive emerging from the slit thereof does not meet the sheets perpen-'i-ifarly and, therefore, does not .have the teni" .-icy to come out in both directions. In other wods, it does not tend to emerge in the direction opposed to that in which the sheets travel, which, with the surfaces to be coated lying advanced in the direction of motion of the sheets, would permit of its entering beneath the advanced edges of the individual sheets. On the contrary, by reason of the described course taken by the outlet slit, the adhesive, on its emergence, already has a direction of flow corresponding and suited to the direction of travel of the layer of sheets. On the other hand, the rounding off or sloping off of the outer surface of the container, starting from the edge of the outlet slit on the side from which the sheets advance and gradually receding from the layer of sheets permits of the unimpeded passage beneath the container of the edges of the sheets which lie advanced in the direction of motion. Furthermore the course of the outlet slit according to this invention affords the advantage that the rear edge of the slit, which the edges of the sheets meet last on their way under the container is blunt, this edge being formed by two planes which meet each other at an obtuse angle. 'I'hus, even under this edge, the sheets can enter Without impact. A slight rounding oft' of the slit-edge in question enhances this favourable effect.

Finally a further advantage is to be observed in the fact that, having regard to the direction of feed of the -stepped layer of sheets, only a narrow strip. of the outer surface of the adhesive container rests on the said layer to the rear of f the outlet slit, while the outer surface of the container behind this strip recedes sharply from the \layer of sheets. When used for so-called plastic gummihg, that is to say, the application of dry adhesive to the work pieces, this arrangement is especially well adapted for preventing freshly applied adhesive, `while still in moist condition, from having to drag beneath and rub leading edgeof this guide plate comes as close as possible to that rounded-off or chamfered-oif outer surface of the adhesive container which immediately precedes the outlet slit. Starting from this leading edge, the surface of the guide plate rests lightly against some'of the stepped sheets and thence recedes quite gradually from the `-layer of sheets. At its rear edge it is spaced from the layer only far enough to ensure that the exposed leading edges of the sheets will run under it. In the case of blanks which, on account of their shape, have to expose a considerable amount of surface behind their coating of adhesive and up to the region where it is possible for them to be engaged by the conveying or delivering means, the guide plate aforesaid both guides and stiffens the exposed surface portion, so that any slight resistance that may act on such surface or upon the leading edge thereof does not immediately cause derangement but can be overcome, notwithstanding the pushing action of the conveying means taking eect at a considerable distance from the leading edge of the sheet.

It is a further object of the invention to provide an arrangement which serves to blow compressed air on to the surface portions of the sheets which liel advanced in the direction of motion of the stepped layer of sheets and have been provided with an adhesive coating. This counteracts the curling up and buckling which frequently takes place at these parts and which may have a particularly harmful effect when, as aforementioned, there is 4a relatively large .area of sheet exposed between the leading edge of each sheet and the means which holds. and delivers it, since these exposed surface portions can easily get out of place in the stepped layer of sheets and give rise to disturbance in working.

'Iwo constructional embodiments of adhesive applying devices in accordance with the invention are shown, by way of example, in Figs. 1 and 2 of the accompanying drawings, each of thesel vice which it depicts. Fig. 3 isa view mainly of the conveying and guide means for the layer of blanks, as seen from the right hand side of Fig. 1 or Fig. 2, the actual adhesive container or gum box being omitted.

The direction of feed of the stepped layer of sheets B is indicated, in all figures of the drawings, by an arrow and is assumed to be such that the adhesive receiving surfaces 2 exposed between the stepwise arranged edges I of the in'- dividualsheets, are the first parts of the sheets to reach the adhesive container 3 or I9. atwhich they arrive edge first, so that, actually the edges I themselves meet the container first. Obviously these edges I must meet and travel past the container without impact and without retardation, if derangement of and damage to the blanks is to be avoided and a satisfactory coating of adhesive obtained. I

'I'he cross-sectional forms depicted in Figs. 1 and 2 of the drawings for the adhesive containers 3 and .I9 are simply in the nature of examples and quite different shapes can be selected without departing fromi the essential features of the invention. Moreover, the means for fixing the `containers 3 and I9 and for pressing them against the-stepped layer of sheets are to be assumed to be known per se and of no importance so far as the present invention is concerned; consequently they are not reproduced in the drawings.

Important features of the invention reside in the arrangement of the outlet slit 4 which is provided in the lower part of the container I of accesary rig. 1 and through which the adhesive, mies inici the container, emerges and reaches the free surfaces 2 of the stepped layerof blanks or sheets B; also in the-formation of the outer surface of 4the container 3 immediately adjoining this outlet slit 4. substantially linear outlet slit 4 is so arranged that its course or path, starting from the interior .l ofthe container and opening on to the layer of the slit 4 a direction of outow suited to the di? rection of. feed of the layer of sheets B and this' '.counteracts the' tendency of the adhesive to penetrate beneath the edges I of the sheets in the To obtain non-impactive entry .of the edges I of the sheets, the outer surface of the container 3, starting from the edge 5 -of the outlet slit 4 l(the lower edge inV the drawings and the one whichisv turned towards the side from which the sheets advance) is -so formed by rounding it of! or inclining it, that it recedes gradually at an acute angle from the layer of sheets B.

vlin-the example shown in Fig. 1 of the drawings,

below the outlet slit 4 and under the actual bot- .tom 6 of the container a special reinforcement 1 is provided whereby a pronounced rounding oi'f 'isobtained under which the edges I of the sheets can comfortably run in without any danger of impact. a

The edge of the outlet slit 4 4which lies uppermiost in the drawings. and beneath` which the edgesI of the sheets'arrive last on 'their way under thecontainer, is formed by the narrow outerA plane surface 9 and the upper internal plane surface of the slit 4, these two planes meeting each 'other'atan obtuse angle a. Thereroi-e, this edge is blunt, which, in itself, favours the non-impactive entry of the sheets... The un- Ahindered entry. of`- the sheets is, however, rmade all the more certain by a' very slight rounding on of this edge of the slit.

Behind the last named edge of the slit, that is to say, on that side ofthe outlet slit 4- which is directed towards the departing portion of the layer of sheets B, only a narrow strip 9 of the. outer surface-of .the container 3 (in fact, a blunt edge) rests on the stepped layer of` sheets,'so that the adhesive applied to the sheet surfaces 2 only needs to pass through under this narrow strip of surface 9 andissubiected to lfriction only by4 this strip, the friction, therefore, being so slight that it cannot have any harmful effect. Behind the narrow strip 8 of the outer surface of the container 9 this\surface' recedes sharply-from' the stepped layer of sheets B. The opening ,9 in the wall of the container 9 serves for filling the latter with adhesive. y When the whole machine and the layer of sheets are temporarily stopped the container does not need to be lifted oi! the said layer, as smearing of the blanks is not, in this case, to be feared. In order to permit of theoutlet slit. 4 being closed up if, for any reason, the container has to be lifted on the layer of sheets, a slide IIIl is provided. It is guided, by

means of slots II, between the washers I2 and the heads I3 of' the screws I4 xed'in the cone tainer wall. lIn an outwardly opening slot I5 in the turned over part I6 .of the slidey I0 there runs a groove formed in a screw I1 the thread of which is engaged in an angle bracket I9 provided on According to the inventionthe There is thus im' the container. l and this screw serves for adjusting the slide I0.

A simpler constructional form of the adhesive container is shown in Fig. 2. This container I9, however, exhibits the same novel features as the container 3 of Fig. 1. Here, again, theslit 20,.

for the outow of adhesive. runs in the direction hereinbefore described and thatpart of the external surface of the container I9 which lies below this slit likewise recedes gradually from the stepped layer of sheets B. Above the slit 29 this container I9 also presents only a narrow strip 2'I of its outer surface in effect, a blunt edge to the layer of sheets B and this narrow strip of surface 2| Alikewise makes an obtuse angle a with the upper internal surface of the slit 29.-

A slide for'shutting off the outlet slit 29 is not vthat 'the stepped sheets B, when they reach the adhesive container 3 or I9, have already been provided, by means of another arrangement, with a coating of adhesive applied to the exposed sur-- face portions on the opposite side of the layer.

The device according to the invention is intended, therefore, for the application of a second coating of adhesive, as required, for instance when employing dry adhesive', as aforesaid. for

A self-sealing articles. `Thus, with certain forms of work pieces, for instance, envelope blanks, as shown in Fig.`3, the conveyor means for the blanks. (that is to say, the conveyor belt 24 and the -counter rol-ls 25 and 26 co-operating therewith, which convey the layer of sheets B from the device which appliesa coating of adhesive to the oneo side thereof, past a device which dries this coating and thence to the adhesive container 3 or I9) are preferably arranged only in the region of the side flaps S of the said blanks; otherwise they would comeinto contact with the coating of adhesive on the reverse side of the closure ap V. This arrangement of the-conveyor means, however; has the drawback that that flap lof each blank which lies advanced in the direc- F tion of motion and which subsequently forms the back part of the finished envelope is free over the whole of its length, as indicated by the dimension 1' in Fig. 3,.when its leading edge is being pushed under thel adhesive container 3 or I9, by means of the belts 24 and the counter rolls 2G. Thus, particularly in the case of thin papers, quite a\ small amount of resistance may causethis flap to ruck up and upset the whole arrange- -ment. In order to counteract this, the guide plate 21 is located ahead of the adhesive contain-v .er 9 or I9 and over thestepped layer of sheets,

in such a way that it overlles practically all'of I the surface of the exposed flap of that blank which, at any given moment, is running in under the said adhesive container and that, within the confines of this surface, it rests lightly upon the layer of sheets. The' guide plate 21, therefore guides and, what is more important, stiifensthe free or exposed flaps of the blanks, thus enabling these aps,lwhen running in under the adhesive container, to overcome any resistance that may arise (so long as it is not extraordinarily great) without being heldup and so rucked orv crumpled.

In Fig. 3 for the sake of clearne. the adhesive vns containeritself is not shown; only the position of its outlet slit in relation to the stepped layer of sheets B is indicated by the` narrow closely sectioned rectangle IV. The surface which lies above this in the figure and which is hatcheddrawings a radially slit ring 281 on the guide plate is fixed, by means of a screw 29 upon a lug 30 projecting from a ring 3|. The last named ring is freely rotatable on a cross shaft 34 upon which it is mounted between two locating rings 33-united by a yoke 32 and which is fixed in the side cheeks of the device although in Fig. 3, for the sake of clearness, it is shown broken away. The locating rings 33 are fixed by the screw 35 to the cross shaft 34. Between an arm 36 on the ring 3| and the yoke 32 which unites the two locating .rings 33 there is arranged a light compression spring 31, so that the ring 3| presses the guide plate 21 against the stepped layer of sheets B. The amount of pressure exerted by-'the spring 31 can be varied, according to requirements, by turning the locating rings 33 upon the cross shaft 34.

The stepped layer of sheets B passes from the conveyor belts 24 to the conveyor belts 38, both of which engage the said layer with the aid of their counter rolls 39, such engagement again as to project the air blast in a direction forming taking place only in the region of the side iiaps S. Between the conveyor lbelts 24 and 38 there is arranged a guide plate 4|, which is fixed to a cross shaft -40 and over which the layer of sheets glides along. The conveyor belts 38 and their counter rolls 39 engage each individual blank atthe exact instant at which it is released by the conveyor belts 24 and the lastcounter rolls 26 of the latter. This is. necessary because the conveyor belts 38 are driven just a little faster than the conveyor belts 24, so that, after the adhesive has been applied, the blanks are drawn apart slightly, in order to prevent them from sticking together along their leading edges. In Fig. 3

this slight drawing apart is made apparent, in the regard to the direction of motion of the stepped' layer of sheets B, that is to say, in a region traversed by the exposed parts of the sheet surfaces which have just been coated with adhesive, there is arranged, at a little distance from the coated surfaces, at least one blower nozzle 42 through which a blast of air, taken from a suit;`

able source, is directed on to the free and exposed marginal parts which have received the coating. vThe nozzle 42, as the drawings show,.is disposed so an acute angle with the direction of travel of the stepped layer and the action of the blast is to force the exposed and free marginal portions, as they pass in succession, firmly against the subjacent sheets in the layer. 'Ihis counteracts the tendency of the adhesive-carrying marginal parts ofthe individual sheets to curl up or buckle, this tendency being more or less apparent according to the kind of paper used for the blanks and its consequence being that the said adhesive coated marginal portions curl away from the layer of l sheets, which may prevent their being conveyed in aregularmanner and so cause them to be damaged. What we claim isz- 1., In apparatus for applying a coating of adi hesive in liquid 'state to paper and similarmaterials and including an adhesive container with an outlet for adhesive and meansfor producing relative wiping action between that surface of the material which is to receive'the adhesive coating and the said adhesive outlet, a container wherein the adhesive outlet is formed as a short duct of narrow slit-like and substantially uniform crosssection extending from the interior of the said container to the material-contacting exterior surface thereof in an upwardly inclined direction,

hesive in liquid state to paper andsimilar materials and including an adhesive container withv an outlet for adhesive and means for producing relative wiping action between that surface .of the material which is-to receive the adhesive coating and the said 'adhesive outlet, a container wherein the adhesive outlet is f ormed as a short duct of narrow slit-like and substantially uniform cross-section extending from the interior of thel j said container to the material-contacting exterior surface thereof in an'upwardly inclined direction, forming an acute angle with'the substantially vertical plane in which the material to be coated travels to and arrives at the adhesive outlet, the exterior 'surface ofsaid container on hesive in liquid state to paper and,similar ma' terials and including an adhesive container with an outlet for adhesive and means for producing relativewiping action between that surface of the material which is to receive the adhesive coating and the said adhesive outlet, a container wherein the Iadhesive outlet Vis formed as a short duct of narrow slit-like and substantially uniform' cross-section extending from the interior of the said container to the material-contacting' exterior surface thereof in an upwardly inclined direction, forming 'an acutevangle with the substantially vertical plane in which the material to be coated travels to and arrives at the adhesive outlet, the exterior .surface of said container on that side of the-adhesive outlet from which the coated material departs comprising onlya nar- -row strip capable of making Contact .with said coated material. V 4. In apparatus for .applying a' coating of' adhesive in liquid state to paper and similar mate.- rials and including an adhesive container with an outlet for adhesive and means for producing relative wiping action between that surface lof the material which is to receive the adhesive coating and the saidadhesive outlet, a container wherein the adhesive outlet isv formed as a short duct of narrow slit-like and substantially uniform crosssection extending from the interior of the said container to the material-contacting exterior surface thereof in an upwardly inclined direction, formingl an acute angle with the substantially vertical plane in which the material to be coated travels to and ar'rives at the adhesive outlet, the exterior surface of said container being shaped.

on that side ofthe adhesive other from which the material to be coated arrives, so' as to recede gradually from the surface of said material and, on that side of the adhesive outlet from which the coated material departs, so as to present only a narrow strip for contact with the coated surface. 5. In apparatus 'for applying a coating-of adhesive in liquid state to paper and similar mate- 4ria1s anadhesive container" having an outlet and substantially uniform cross-section proceeding y'from the interior toA the exterior surface of the adhesivecontainer in an lupwardly inclined direction, forming an acute angleswith the substantially vertical plane in Awhich the uncoated material travels to and arrives at the said. adhesve outlet. .r

`6; In apparatus forapplying a coating of adhesive in liquid state to paper and similar articles arranged in stepped formation vin a continuous layer, Aso, that a defined surface portion of leach article is exposed for coating, lthe combination with an adhesive container having a narrow outlet slit for adhesive andmeans for producing relative wiping action between theoutlet slit of the container and that composite surface of the `stepped layer of -articles'which is to receive.

the adhesive coating, of guide means actingdirectly upon the said composite surface in a zone preceding" and immediately adjacent to the zone` of application of the adhesive issuing from the slit and supporting means for said stepped ,layerI bf articles, -said supporting means confronting both the adhesive outlet of the container and the guidemeans.A

'1. The apparatus defined in claim 6, further 'characterizedby the said guide means comprising V4.aplate pressed yieldingly against the said composite surface to be provided with the adhesive coating.

8. The apparatus 'donned -in claim 6, further 56 characterized by the said guide means comprising i aplate detachably associated with means for pressing it yieldingly-against the said composite .surface to be provided with the, adhesive coating.

9. In apparatus for applying acoa'ting-of ad.l

'I -I'hesve in liquid state, to paper and similar articles .arranged in stepped formation in a continuous layer, so that a defined marginal portion of each article is `left free with one surface exposedV for coating, the combination with an adhesive container having a narrow outlet slit for adhesive and means for producing relative wiping ac.

tion between the outlet slit of the container and the exposed; composite surface formed by the' said free marginal portions lfof vthe articles in the stepped layer, of guide means acting directly upon the said exposed composite surface lin a zone preceding and immediately adjacent to the zone v `0f-applioation. of the adhesiveissuing from' the Y slit, supporting means for said stepped layer of articles, said supporting means directly confronting both the adhesive outlet of the container and the guide means,` and means for projecting against said free marginal portions of said layer,

in a direction forming an acute angle with the ldirection of travel of said layenan air blast adapted to impinge on the successively passing free mar-gina1 portions and to pressthem firmly -each against the corresponding subjacent Asheet in the layer. l

10.` In .apparatus for applying a coatingofad- -vhesive in liquid state to paper and similar artif cles arrangedin stepped formation in a continuous layer, so that a denedsurface portion ofA each article 'is'exposed for coating, an adhesive container having an outlet for adhesive, means for supporting the said layer of articles, so that the stepped composite surface receiving the adhesive coating comes in close juxtaposition to the said adhesive outlet,means.for producing relative wiping action between saideadhesive outlet and said composite surface and guide means acting upon said composite surface 4in a zone preceding that in' which it receives. the adhesive, said adire-l sive outlet consisting of a duct of narrow, slitlike cross-section proceeding from the interior 'y to the exterior surface of the adhesive container in a direction forming an acute angle with the direction from which the stepped layer ofl un.

coated articles arrives at vthe said adhesive outlet and presenting a substantially linear slit-like opening in contact with said layer of articles, .that

side of the said opening over which-the layer passes after receiving the coating being bounded by a blunt edge from which the external surface of `the container recedes sharply, leaving only a 7 vlinear strip of the container surface for contactA with the coated composite surface'of the layer; 11'. The apparatus definedin claim 1 0, characterized by the said supporting means'. being orpath of travel of said layer to the adhesive applying zone and further characterized .by theex- .ternal surface vof the container adjacent the -slit-like adhesive outlet being shaped to yrecede `gradually `from the said supporting means and,

"therefore, from the uncoated composite layer sur-v face, on that side of the said adhesive outlet from -whicnthe layer arrives.

i2. The apparatus dennen 1n claim 1o, fur ther characterized by the external surface of the adhesive container on that side of the slit-like adhesive outlet from which the uncoated stepped layer "ofa'rticles arrives being shaped to recede gradually from the adhesive receiving composite surface of-said layer, by the guide means acting on. sucnsurface consisting of a platelikentember ganized to support the stepped layer along the having'an edge portion disposed 'closely' adjacent said' recedinge'xternal surface portion of said container,"by supporting means forl said plate- .like member and vby means associated with saidA supporting means for'causing said edge portion o f said plate-like member to press yieldingly upon c the surface parts of the layer about to come into co-operation with the slit-like adhesive outlet.

WINKIER. MAX piiuuiazensn.y 

